Hi Ravi,
You said the users are comparing the Webi report with PeopleSoft reports. I am unaware on how PeopleSoft captures the data from Oracle.
To troubleshoot in Webi try this:
1. Edit the report and capture the SQL from Query Panel.
2. Check the database user which has been used to create the universe connection.
3. Log onto Oracle SQL Plus with same user.
4. Paste the query and execute.
Do you get the data in email-id column?
Regards,
Yuvraj